Template:Convert/numdisp

The Template:Convert/numdisp processes a number, for display, by checking to display a fraction part (at "/"), else it just uses parser-function {{formatnum:{{{1|6000}}}}} to add commas, such as to show "6,000". In 99% of recent Wikipedia usage, there are relatively few articles using fractions (less than 1% of articles using Convert show fractions).

The check, for fraction parts, uses parser-function {{#titleparts:xx/xx|1|2}} to split a number at "/" (if any, as in: 6+3/8) and then checks if part 2 (the denominator, after the slash) contains a number, to trigger use of {{Convert/numdisp/frac}}). Hence, the template uses:

#if: {{#titleparts:{{{1|6+3/8}}}|1|2}}

That if-expression will be true if a denominator exists (such as "8" in 6+3/8).